/Engine/Source/Editor/UnrealEd/Public/Kismet2/KismetDebugUtilities.h
Looks thru the debugging data for any class variables associated with the pin.
static [FProperty](API\Runtime\CoreUObject\UObject\FProperty) * FindClassPropertyForPin ( [UBlueprint](API\Runtime\Engine\Engine\UBlueprint) * Blueprint, const [UEdGraphPin](API\Runtime\Engine\EdGraph\UEdGraphPin) * Pin )